Ni^2—交换蒙脱石中的镍物种及焙烧温度影响研究

对一组自制Ｎｉ＾２＋交换蒙脱石样品中镍物种的存在在形及焙烧温度影响进行了ＴＰＲ和ＸＲＤ考察结果表明，样品中镍负载量等于或小于Ｎｉ＾２＋的交换量时，镍主要以难还原听可交换性阳离子Ｎｉ（ＯＨ）＾ｑ＋ｘ和易还原的自由态镍Ｎｉ（ＯＨ）２或ＮｉＯ两种形式存在。

STUDIES OF THE EFFECT OF CALCINATION TEMPERATURE ON THE Ni SPECIES IN Ni 2+ EXCHANGED MONTMORILLONITE

Ni species and the effects of calcination temperatures on them are studied by means of TPR and XRD for a group of samples of Ni 2+ exchanged montmorillonites.The results show that only exchangeable cation Ni(OH) q+ x occurs in the samples when Ni loadings on the samples are equal to or less than the Ni 2+ exchange content,and two species,exchangeable cation Ni(OH) q+ x and free state Ni(OH) 2 (the latter is a state easy to reduce and the former is a state hard to reduce),occur in the samples simultaneously when Ni loadings on the samples are more than the Ni 2+ exchange content.all Ni species in the samples can migrate into the framework structure of montmorillonite after sufficient calcination,but the difficulty of the migration is different for these Ni species:exchangeable Ni